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All Journal Reaktor TEKNIK METANA JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Bulletin of Chemical Reaction Engineering & Catalysis Seminar Nasional Teknik Kimia Kejuangan Majalah Ilmiah MOMENTUM Indonesian Journal of Chemistry Jurnal Pasopati : Pengabdian Masyarakat dan Inovasi Pengembangan Teknologi Jurnal Rekayasa Kimia & Lingkungan International Journal of Renewable Energy Development Bulletin of Chemical Reaction Engineering & Catalysis
Bakti Jos
Departemen Teknik Kimia, Fakultas Teknik, Universitas Diponegoro, Kampus Undip Tembalang Jl. Prof. Soedarto, SH, Semarang, Indonesia 50275
Aerospace Engineering Automotive Engineering Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Civil Engineering, Building, Construction & Architecture Computer Science & IT Control & Systems Engineering Earth & Planetary Sciences Education Electrical & Electronics Engineering Energy Engineering Environmental Science Industrial & Manufacturing Engineering Materials Science & Nanotechnology

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OPTIMALISASI EKSTRAKSI DAN UJI STABILITAS PHYCOCYANIN DARI MIKROALGA Spirulina platensis Jos, Bakti; Eko Setyawan, Prayudi; Satria, Yudha
TEKNIK Volume 32, Nomor 3, Tahun 2011
Publisher : Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (334.469 KB) | DOI: 10.14710/teknik.v32i3.1734

Abstract

The growing awareness of the importance of natural colours especially food and cosmetic colorants has placedgreat demand on biological sources of natural colours. It is for this reason that the phycobiliproteins inSpirulina platensis is gaining increasing attention as an alternative colour for these products. Numerousscientific reports confirm the fact that Phycocyanin from Spirulina platensis, is not only an effective naturalblue colorant, but also a compound that is beneficial to the health of the consumer. The aim of this research is toconduct evaluation studies phycocyanin production by extraction with polar solvents at various concentrationsto obtain extracts for maximum yield. The methods in this study has several stages, namely preparation ofmaterials, extraction, solubility studies of phycocyanin, phycocyanin’s stability test. Changing variables in thisstudy are water, acetic acid 70%, 75%, 80%, ammonium sulphate 50%, 55%, 60%. The analysis of the extractsof phycocyanin’s content using spectrophotometric methods. The observations produces a blue pigment whichhas the highest color intensity with maximum absorbance of 620 nm. Acetic acid 80% is the most effectivesolvent to extract the blue pigment phycocyanin than water and ammonium sulfate. Extraction is influenced bythe pH of the increase in absorption (absorbance) with increasing pH and was not influenced by storagetemperature and time
PENGGUNAAN MEMBRAN ULTRAFILTRASI DALAM PEMBUATAN SARI BUAH RAMBUTAN JOS, BAKTI; Susanto, Heru; Kuntolaksono, Satrio; Ariyanto, Yanuar
METANA Vol 6, No 02 (2010): Desember 2010
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (67.421 KB) | DOI: 10.14710/metana.v6i2.3430

Abstract

Abstract   Hairy fruit (Nephelium sp) is fruit of horticultural belong in family Sapindacaeae. Membrane is a thin layer separates two phases which allow the displacement of specific components and hold other components that do not being needed. Ultrafiltration is a filtration process using membranes that filter out particles with a size of 20 to 1000 Angstrom. Results of ultrafiltration has high purity (0.4 to 0.6 NTU turbidity) than results from conventional manner (1.5-3 NTU turbidity). Yield gained was 5-8% higher than that gained from conventional. Dependent variable used is kind of hairy fruits (crops and cans). The independent variable is the pressure 2 kg/cm2, 3 kg/cm2, 0.4 kg/cm2, 0.5 kg/cm2, 0.6 kg/cm2 and the type of membrane (PES and hydrosart). The result of the study showed that greater operation pressure resulted in greater turbidity, and greater flux. The greater flux resulted smaller selectivity and pass the requirement of Environmental Protection Agency, USA.   Key word : Hairy fruits, juice, membrane, ultrafiltration
EKSTRAKSI ASAM LEMAK OMEGA - 3 DARI LIMBAH IKAN TUNA Jos, Bakti
METANA Vol 3, No 2 (2006): Juli 2006
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (4396.6 KB) | DOI: 10.14710/metana.v3i2.1804

Abstract

Abstract Tuna waste still have a valuable substance that is fish oil, which contains omega-3 fatty acid. Omega-3 is polyunsaturated fatty acid, consist of two acid, eicosapentaenoic acid (EPA) and  dokosahexanoic acid (DHA). Omega-3 fatty acid has many usefulness for human’s health, related to heart, retina, and brain function. This research is done to get omega-3 fatty acid from tuna waste by extraction method using n-hexane. The purposes of the research are to learn about variables that affect the product and decide the condition to get optimal product. The research method is making table and chart from the variables. The condition of the operation are : temperature ± 30oC, solvent n-hexane, KOH concentration is 40 gr/liter, and concentration of oil in feed is 0.068 gr/cc. The variables are : comparison of solvent and feed (10:4; 15:4; 20:4; 25:4; 30:4; 35:4) at period 1,5 jam, and period of extraction (0,5; 0,75; 1; 1,25; 1,5; 1,75 jam) at comparison of solvent and feed 30:4. The result shows that the optimal condition is reached at comparison of solvent and feed 30:4 and period of extraction 1,5 hour. The rendement is 24,76%. Key words : tuna, omega-3, extraction
Studi Kinetika Hidrolisis Enzimatik Pati Singkong: Pengaruh Perbandingan Alfa-Amilase dan Glukoamilase Terhadap Gula Reduksi Hargono Hargono; Andri Cahyo Kumoro; Bakti Jos
Prosiding Seminar Nasional Teknik Kimia "Kejuangan" 2018: PROSIDING SNTKK 2018
Publisher : Seminar Nasional Teknik Kimia Kejuangan

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Application of Glyoxal Acrylamide Modified Κ-Carrageenan as A Superabsorbent Polymer in Drug Delivery System Aji Prasetyaningrum; Al Farrel A. Raemas; Nur Rokhati; Bakti Jos
Reaktor Volume 20 No.3 September 2020
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (835.098 KB) | DOI: 10.14710/reaktor.20.3.150-158

Abstract

The hydrogel is superabsorbent polymers (SAP) that are biodegradable and can be obtained from polysaccharides, lipids, and proteins. Polysaccharides include cellulose, starch and their derivatives, seaweed extracts such as carrageenan, alginate, pectin, and chitosan. Carrageenan is the result of the extraction of red seaweed sap with an alkaline solution. The main objective of this study was to simultaneously increase the strength and properties of κ-carrageenan SAP film with the addition of glyoxal and acrylamide as crosslinkers. The addition of acrylamide (variated from 1 to 7 % b/v) into the k-Carrageenan based SAP hydrogel compound and the presence of glyoxal as crosslink agent (variated from 0 to 1,0 % v/v). The physical properties of the SAP films were analyze using swelling degree and tensile strength. The structural and morphological properties of composite films were analyzed using Fourier Transform Infrared (FTIR) and Scanning Electron Microscopy (SEM). In addition, the effect of pHs on the releasing drug Poly(vinylpyrrolidone)-Iodine was investigated. This research shows that the addition of acrylamide and glyoxal can improve the physical properties of the modified κ-carrageenan film. Characterization using SEM shows that the addition of glyoxal causes the formation of tissue fibers in SAP. FTIR spectra indicated the formation of cross bonds in modified SAP film at 3294.42 cm-1 (carboxylic acid). The treatment under alkaline conditions will increase drug release ability.Keywords: κ-carrageenan; hydrogels; acrylamide; glyoxal; drug delivery
Effect of Esterification on Cassava Starch: Physicochemical Properties and Expansion Ability Siswo Sumardiono; Listiyana Riska; Bakti Jos; Isti Pudjiastuti
Reaktor Volume 19 No. 1 March 2019
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (459.331 KB) | DOI: 10.14710/reaktor.19.1.34-41

Abstract

In this study, the characteristic of cassava starch have been developed through esterification reaction using ethyl lactate. Commercial cassava starch was modified by using (0.5; 0.75; 1.00; 1.25; 1.50 % v/v) ethyl lactate solution with pH 6, 7, 8, 9 for 15, 25, 35, 45, 55 minutes and the drained starch was dried with sun drying. The cassava starch which has been esterified with 1.5% ethyl lactate for 15 minutes pH 6 gave highest volume expansion of 2,438.9 %. For swelling power, the highest value was 19.32 swelling power at variable concentrations of 1.5% ester, esterification period of 15 minutes, and pH 6. The lowest amylose content was 15.68 % in ester concentration of 1.5 %. From the scanning electron micrograph, shows that the cassava starch after and before modification has not changed since the modifications performed under the gelatinization temperature. FTIR spectra of native cassava starch and ester cassava starch shown shift of the carboxyl group of starch from 1072.37 to 1087.80 cm-1 and a decrease in the OH group is from 3452.53 to 3417.81 cm-1. Bond formed indicates that the esterification reaction occurs between cassava starch with ethyl lactate esters. Keywords: volume expansion, cassava starch, ester starch, ethyle lactate, modified starch
EKSTRAKSI OLEORESIN DARI KAYU MANIS BERBANTU ULTRASONIK DENGAN MENGGUNAKAN PELARUT ALKOHOL Bakti Jos; Bambang Pramudono; Aprianto Aprianto
Reaktor Volume 13, Nomor 4, Desember 2011
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (65.961 KB) | DOI: 10.14710/reaktor.13.4.231-236

Abstract

ULTRASOUND ASSISTED EXTRACTION OF CINNAMON OLEORESIN FROM CINNAMON BARK USING ALCOHOLS AS SOLVENTS. Cinnamon oleoresin is a complex mixture of resin and essential oil extracted from cinnamon burmanii by using organic solvent, and is primarily used as a coloring and flavoring in food products. Major component in essential oil is cinnamic aldehyde. Extraction was usually performed by percolation or soxhlet with various solvents. Several studies on the extraction of oleoresin have been completed by using polar organic solvents. Generally Recognized as Safe (GRAS) solvents, which are safe to use in food, were considered as alternative extraction solvents. Hildebrand solubility parameter concept was also used to choose the solvent. In this research, oleoresin from cinnamon was extracted by using ultrasound assisted extraction. Methanol, ethanol and isopropyl alcohol were used as the solvent to determine the extraction time, extraction rate and the kinetic model correspond to the yield of oleoresin. The result showed that the optimal time and extraction intensity are 66 minutes and 20% respectively, oleoresin yield by using solvent extraction of methanol, ethanol, and isopropyl alcohol were 22.86%, 17.87%, and 14.64% respectively. The results were similar compared to conventional extraction. Kinetic study confirmed that the second-order kinetic model is suitable for this research and the extraction rate constant for the second-order kinetic model of these solvents were 0.098, 0.057, and 0.089 respectively.  Abstrak  Oleoresin kayu manis merupakan campuran komplek antara resin dan minyak atsiri sebagai hasil ekstraksi kayu manis dengan menggunakan pelarut organik. Oleoresin banyak digunakan sebagai pewarna dan flavor dalam industri makanan. Komponen utama dalam minyak atsiri kayu manis adalah cinnamic aldehyde. Pada umumnya ekstraksi kayu manis menggunakan cara perkolasi atau soxhlet dengan berbagai pelarut. Beberapa studi ekstraksi oleoresin yang telah dilakukan, menunjukkan bahwa penggunaan pelarut polar lebih baik dibandingkan pelarut non polar. Pemilihan pelarut yang digunakan untuk ekstraksi harus mempertimbangkan pelarut GRAS (Generally Recognized as Safe) dan juga parameter kelarutan Hildebrand. Penelitian ini menggunakan metanol, etanol, dan isopropil alkohol sebagai pelarut untuk mengekstraksi oleoresin dari kayu manis yang menggunakan ultrasonik. Tujuan penelitian ini adalah menentukan pengaruh waktu dan intensitas ekstraksi berbantu ultrasonik dan juga menentukan model laju ekstraksi. Hasil penelitian menunjukkan bahwa waktu optimal dan intensitas optimal masing-masing adalah 66 menit dan 20%, sedangkan kadar oleoresin yang dihasilkan dengan pelarut metanol, etanol, dan isopropil alkohol berturut-turut  sebesar 22,86%, 17,87%, dan 14,64%, dimana hasil ini relatif sama dengan hasil ekstraksi dengan menggunakan metode konvensional. Studi kinetika menunjukkan bahwa model laju ekstraksi orde dua lebih sesuai untuk penelitian ini dan dari hasil penelitian diperoleh nilai konstanta laju ekstraksi, k berturut-turut 0,098; 0,057; dan 0,089
Encapsulation of Lemongrass Extract (Cymbopogon citratus) Coated Alginate/Chitosan Using Gelation Method Aji Prasetyaningrum; Sadam Arrois; Fitri Lafifa; Aat Zaki Mubarok; Fadlillah Fani; Noer Abyor Handayani; Ratnawati Ratnawati; Bakti Jos
Reaktor Volume 21 No. 3 September 2021
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (489.034 KB) | DOI: 10.14710/reaktor.21.3.124-132

Abstract

Lemongrass (Cymbopogon citratus) is a medicinal plant with various biological activities such as antibacterial, antifungal, antiprotozoal, anti-inflammatory, and antioxidant. This study aimed to encapsulate lemongrass bioactive in alginate/chitosan complex by enhancing the properties of CaCl2 crosslinked incorporated with tween 80 by ionic gelation method. The hydrogel was prepared by mixing alginate solution (2% w/v) and chitosan solution (1% w/v) with a ratio (1:1 v/v). Tween 80 (2% v/v) was added as a dissolution enhancer and CaCl2 as a crosslinker agent. The formulation varying by concentration of CaCl2 (0.1M to 0.3M) and lemongrass extract (2% to 12%). Encapsulation lemongrass with alginate-chitosan beads is characterized to determine encapsulation efficiency, swelling study, morphology, functional groups, and release study. The results showed that encapsulation efficiency ranged from 74.81% to 83.07%. Encapsulation efficiency increased with the addition of CaCl2 and lemongrass extract concentration. The swelling ratio ranged from 27.29 to 37.81, it will decrease with the addition of CaCl2 and lemongrass extract concentration. The Scanning Electron Microscopy (SEM) analysis of hydrogel beads shows a polyhedral shape, porous, and rough surface which indicates bioactive of lemongrass trapped on the beads. The Fourier Transform Infrared Spectroscopy (FTIR) results show new peaks at 1734 cm-1 as carbonyl stretch vibrations in ketones, aldehydes, and carboxylic acids, indicating the addition of lemongrass extract. Bioactive of lemongrass extract loaded alginate-chitosan beads was successfully released as much as 87.12% at pH 6.8. This study suggested the strong potential alginate-chitosan beads as an encapsulating agent for lemongrass extract using the ionic gelation method, and it has potential as a drug delivery system.Keywords: encapsulation; lemongrass; alginate; chitosan; CaCl2
Optimasi Proses Ozonasi pada Depolimerisasi κ-Karagenan dengan Metode Respon Permukaan Aji Prasetyaningrum; Ratnawati Ratnawati; Bakti Jos
Reaktor Volume 17 No.1 Maret 2017
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (402.829 KB) | DOI: 10.14710/reaktor.17.1.1-8

Abstract

Abstract OPTIMIZATION OF OZONATION PROCESS FOR κ-CARRAGEENAN DEPOLYMERIZATION USING RESPONSE SURFACE METHODOLOGY. The objective of this research is to optimize the operating parameters in depolymerization of κ-carrageenan by ozone treatment. The optimization is done by using Box-Bhenken Design (BBD) model with ozonation time (5-15 minute), pH (3-11) and temperature (20-40oC) as the independent variables.The response of ozonation process is the degree of depolymerization of κ-carrageenan (DP). The initial molecular weight of refined κ-karagenan was 271 kDa. The κ-carrageenans powder was completely dissolved in distilled water to form 1% (weight/volume). The experiments were carried out in a 2000 ml of a glass reactor with an ozone gas sparger. The inlet ozone concentration was 80±2 ppm. The result shows that ozonation time, pH and temperature have significant effects during ozonation process (p< 0.05). Analysis of variance shows that the experimental data fit the model very well with the R2 value of 0.98. The optimum conditions during ozonation process are achieved at the reaction time of 15 min, ozonation pH of 3 and reaction temperature of 25oC. Under these optimum conditions the DP of κ-carrageenan is 91.513%. Keywords: depolymerization; κ-carrageenan;optimization; ozonation process   Abstrak Tujuan penelitian ini adalah menentukan kondisi optimum parameter operasi depolimerisasi κ-karagenan dengan perlakuan ozonasi. Optimasi dilakukan dengan menggunakan model statistika Box-Bhenken Design (BBD) dengan variabel yang digunakan yaitu waktu ozonasi (5-15 menit), pH (3-11), dan suhu (20-40oC). Respon dari proses ozonasi adalah derajat depolimerisasi κ-karagenan (DP). Berat molekul awal refined κ-karagenan adalah 271 kDa. Sampel κ-karagenan dilarutkan secara sempurna dalam air distilasi dan konsentrasi diatur 1% (berat/volume). Percobaan dilakukan dalam reaktor gelas volume 2000 ml yang dilengkapi dengan sparger gas ozon. Konsentrasi gas ozon yang masuk adalah 80±2 ppm. Hasil penelitian menunjukkan bahwa waktu ozonasi, pH, dan suhu berpengaruh secara signifikan terhadap proses ozonasi (p<0,05). Analisis varian menghasilkan ketelitian yang tinggi antara data eksperimen dan prediksi, dengan nilai koefisien R2 = 0,98. Kondisi optimum diperoleh pada waktu ozonasi 15 menit, pH ozonasi 3 dan temperatur reaksi 25oC. Pada kondisi optimum ini diperoleh DP κ-karagenan sebesar 91,513%. Kata kunci:depolimerisasi; κ-carrageenan;optimasi; proses ozonasi 
Kinetics and equilibriums adsorption of Cu (II) ion by chitosan and cross-linked chitosan-bentonite Hargono Hargono; Angga Mei Sarah; Feninda Nevrita; Bakti Jos
Reaktor Volume 19 No. 3 September 2019
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (320.152 KB) | DOI: 10.14710/reaktor.19.3.117-124

Abstract

The sorption of Cu (II) particle from aqueous solution onto chitosan and cross-connected chitosan-bentonite (CTS-BTN) as adsorbent were conducted in batch conditions. The impact of different test parameters: starting pH, sorption time was assessed. Equilibrium studies have been completed to decide the limit of chitosan and CTS-BTN for Cu (II) particle. The Langmuir and Freundlich isotherm models were used in the examination of the trial information as linearized conditions. It was discovered that the isotherm information were all around portrayed by the Langmuir isotherm. Chitosan and CTS-BTN showed an adsorption capacity of 125 mg/g and 142.86 mg/g, respectively. The constant of adsorption rate was investigation utilizing a pseudo first order and a pseudo second order model. The pseudo second order model brought about the best fit with test information (R2= 0,991 for CTS and R2= 0,995 for CTS-BTN), additionally giving a constant rate k2, ads= 8.85 x 10-5 g/mg min for CTS and 3.72 x 10-4 g/mg min for CTS-BTN. Recommending that this model could be used in design and applications.Keywords:  adsorption; Cu(II) ion; chitosan; cross-linked; isotherm; kinetics
Co-Authors . Widayat A Abdullah Aat Zaki Mubarok Abdullah Abdullah Aji Prasetyaningrum Al Farrel A. Raemas Andri Cahyo Kumoro Angga Mei Sarah Aprianto Aprianto Bambang Pramudono Dessy Ariyanti Dessy Ariyanti Diah Susetyo Retnowati Dyah Hesti Wardhani Fadlillah Fani Feninda Nevrita Fitri Lafifa Gian Restu Prinanda Hantoro Satriadi Hargono Hargono Hargono Hargono Hargono Hargono Hargono Hargono Hargono Hargono Hargono Hargono Heri Cahyono Heru Susanto Isti Pudjiastuti Jonathan Ginting Listiyana Riska Muchlis Riki Darmawan Muhammad Fahmi Zakaria Noer Abyor Handayani Nur Rokhati Patrick Andreas Praditya Nugraha Prayudi Eko Setyawan Prayudi Eko Setyawan Ratnawati Ratnawati Sadam Arrois Satrio Kuntolaksono Siswo Sumardiono Suherman Suherman Sukaryo Sukaryo Teguh Riyanto Teguh Riyanto Widayat Widayat Y Yufidani Yanuar Ariyanto Yudha Satria Yudha Satria Yudhy Dharmawan